Quick gun:
At the start of the game, run though the back door to a gun faster and safer than 
going to the man at the front. Note: Hit him in the head and he will die faster.

Better sniping accuracy:
When in sniper mode, zoom in. To steady yourself for greater accuracy, sit there 
and do not touch anything to look or move for about five secounds or until he 
stops moving around. You can now look around with perfect dead aim accuracy.

More ammunition:
Wait until an enemy reloads his weapon before killing him. Kill him before he fires 
his gun and you will get a full magazine for your weapon.

Ubisoft logo:
When you first start the FBI level, immediately after the woman shoots out your 
cuffs, go to the center of the room with the three computers. You will find the 
Ubisoft logo acting as a screensaver.

If you walk up to the computer screen, look down at it, and press A, the screen 
will say "GAME OVER".

Automatic crosshair centering:
Click the Right Analog-stick to automatically center the crosshair at head height. 
This is useful on levels with lots of enemies and Xbox Live.

Surviving against experienced online players:
Online play can be seriously difficult for those skipping the single player mode and 
going straight to multiplayer on Xbox Live. Experienced players seem to take a lot 
of hits while they shoot minimal bullets to kill you. Try the following strategies. 

Get the Kevlar Vest for 100 points for extra protection. 
Get five helmets for 20 points each, protect your head. 
Get the M16 with grenade launcher or the submachine gun (RP-46) for maximum 
damage with minimal shots. 

Do not stand still; move around and shoot to avoid direct hits. Also, aim for the 
head. 

If you are low on health and body protection, detach from engaging and get your 
armor and health back up quickly.